Method and apparatus for improving loop stability and speed of a power control loop

A base station, comprising:

• input and output filters for filtering signals received and transmitted via an air interface to a mobile station;
• a transceiver, coupled to the input and output filters, for receiving filtered signals from the input filter and for transmitting signals to the output filter;
• a processor, couple to the transceiver, for providing digital signal processing to signals provided to and received from the transmitter;
• a transmission system, coupled to the processor, for providing an interface between the processor and an Abis interface;
• and
• an operation and maintenance unit, coupled to at least the transceiver and the processor, to administer the functionality of at least the transceiver and the processor and to provide clock distribution to at least the transceiver and the processor;
• wherein the transceiver further comprises a power control loop for reducing adjacent channel interference in a ramp-up and a ramp-down of a signal burst generated by the base station, the power control loop including a loop bandwidth and further comprising:
• a first amplifier for receiving an input signal and generating a power output signal in response thereto;
• a coupler for sampling the power output signal;
• a detector/linearizer circuit, coupled to the coupler, for generating a voltage signal;
• a comparator, coupled to the detector/linearizer circuit, for receiving the voltage signal and comparing the voltage signal to a reference signal to generate an error signal;
• a variable gain amplifier, coupled to the comparator, having a selectable gain, the variable gain amplifier receiving the error signal to produce a controller input signal according to the gain;
• a gain controller, coupled to the variable gain amplifier, for ramping the gain of the variable gain amplifier by processing the reference signal;
• and
• a controller, coupled to the variable gain amplifier, the controller receiving the controller input signal and generating a control signal to control attenuation of the input signal to the first amplifier, wherein the ramping of the gain of the variable gain amplifier provides a constant loop bandwidth of the power control loop without regard to the power level of the sampled power output signal.